The present invention relates generally to structural members which are used in the construction of a vehicle body. More particularly, the present invention relates to that portion of the vehicle body which carries or encloses a person at the location on the body where the operation of the vehicle is controlled including constructional elements of the cab such as a framework or panel or joint or such similar element. Specifically, the present invention relates to the roof portion of the cab structure having means for the treatment of cab atmosphere, such as heating, cooling or ventilating the air within the cab.
It is well known that work vehicles such as agricultural tractors and equipment as well as construction equipment are frequently operated in less than ideal environmental conditions. For example such equipment is often operated in uncomfortably warm or cold weather and in dusty conditions caused by the work being done by the vehicle. It has thus been desired to provide operator""s stations in such vehicles which insulate the operator from such adverse environmental conditions by filtering and conditioning the air inside the cab. One approach has been to dispose the components of an HVAC system in a housing having air inlet and outlet apertures. The housing is then mounted to the vehicle roof or installed into the roof structure. This results in a cumbersome structure which does not optimize the available space and frequently intrudes into the operator""s station impairing the free movement of the operator and sometimes obstructing the operator""s field of view. Similarly, the ducts, hoses, conduits, wiring and inlet and outlet vents are typically positioned based upon available space rather than efficient ergonomic placement.
Previous attempts at overcoming these disadvantages have involved the use of one piece roto-molded roof structures which have a well or compartment formed therein to receive the HVAC unit and having air ducts and vents molded into the roof structure. Such attempts have created their own disadvantages. For example, roto-molded parts do not have a high degree of dimensional stability and thus present a number of fit, mount-up, and aesthetic difficulties. Further, one piece designs do not allow access for servicing, and present difficulties in the routing of conduit and wiring.
Accordingly, there is a clear need in the art for a molded roof structure for a work vehicle which incorporates the components of an HVAC system into the structure itself in a way that facilitates servicing, routing of lines, and ergonomic placement of ducts and vents.
In view of the foregoing, it is an object of the invention to provide a two piece roof structure having the necessary intakes, ducts and vents for the HVAC system formed therein.
Another object of the invention is the provision of a two piece roof structure having means for housing the HVAC components within the roof itself.
A further object of the invention is to provide a two piece roof structure which facilitates servicing of HVAC components and routing of HVAC lines.
An additional object of the invention is the provision of a two piece roof structure which can be compression molded using known techniques.
The foregoing and other objects of the invention together with the advantages thereof over the known art which will become apparent from the detailed specification which follows are attained by a two piece vehicle roof structure comprising: a lower roof member; a core chamber formed in the lower roof member; at least one HVAC core disposed in the core chamber; at least one fresh air duct molded in the lower roof member; at least one first air intake aperture in the fresh air duct; at least one first filter element removably mounted in the first air intake aperture; at least one unconditioned air duct communicating between the fresh air intake aperture and first filter element and the HVAC core chamber; at least one second air intake aperture in the unconditioned air duct; at least one second filter element removably mounted to the second air intake aperture; at least one conditioned air duct formed in the lower roof member; at least one conditioned air vent in the conditioned air duct; at least one blower disposed in the core chamber, the blower having an inlet and an outlet, the inlet drawing air from the core chamber and the outlet expelling air into the conditioned air duct; and, an upper roof member mounted to the lower roof member to enclose the core chamber, the unconditioned air duct, and the conditioned air duct to form discrete air passages between the roof members.
Other objects of the invention are attained by a two piece vehicle roof structure comprising: an upper roof member; a lower roof member having an upper side and a lower side; a core chamber formed in the lower roof member; at least one HVAC core disposed in the core chamber; at least one fresh air duct molded in the lower side of the lower roof member; at least one fresh air intake louver removably mounted to the fresh air duct; at least one first air intake aperture in the fresh air duct; at least one fresh air filter removably mounted in the first air intake aperture; at least one fresh air dust tray removably mounted to the fresh air duct; at least one unconditioned air duct communicating between the fresh air intake aperture and fresh air filter and the HVAC core chamber; at least one second air intake aperture in the unconditioned air duct; at least one recirculated air filter removably mounted to the second air intake aperture; at least one conditioned air duct formed in the lower roof member; at least one conditioned air vent formed in the conditioned air duct; and, at least one blower disposed in the core chamber, the blower having an inlet and an outlet, the inlet drawing air from the core chamber and the outlet expelling air into the conditioned air duct; wherein the upper roof member is mounted to the lower roof member to enclose the core chamber, the unconditioned air duct, and the conditioned air duct to form discrete air passages between the roof members.
Still other objects of the invention are attained by a two piece roof structure for enclosing one or more sidewalls to define a vehicle cab comprising: a lower roof member; a core chamber formed in the lower roof member, the core chamber having at least one condensate well and drain; at least one HVAC core comprising heating and cooling elements disposed in the core chamber, the HVAC core having input and output lines; at least one fresh air duct molded in the lower roof member; at least one fresh air intake louver removably mounted to the fresh air duct; at least one first air intake aperture in the fresh air duct; at least one fresh air filter removably mounted in the first air intake aperture; at least one fresh air dust tray removably mounted to the fresh air duct; at least one unconditioned air duct communicating between the fresh air intake aperture and fresh air filter and the HVAC core chamber, wherein the lines of the HVAC core are routed through the unconditioned air duct; at least one second air intake aperture in the unconditioned air duct; at least one recirculated air filter removably mounted to the second air intake aperture; at least one conditioned air duct formed in the lower roof member, the conditioned air duct having a duct cover affixed thereto; at least one conditioned air vent formed in the conditioned air duct the conditioned air vent having a control louver affixed thereto; at least one blower disposed in a contoured blower area of the core chamber, the blower having an inlet and an outlet, the inlet drawing air from the core chamber and the outlet expelling air into the conditioned air duct, wherein the lower roof member includes a partition wall adjacent to the blower area for routing air from the unconditioned air duct through the HVAC cores; an upper roof member having at least one removable access panel covering at least one access aperture mounted to the lower roof member to enclose the core chamber, the unconditioned air duct, and the conditioned air duct to form discrete air passages between the roof members, the upper roof member and lower roof member having a mastic seal interposed therebetween, and wherein one of the one or more sidewalls defining the vehicle cab are interposed between the first air intake aperture and the second air intake aperture so that the first air intake aperture receives air from outside the cab and the second air intake aperture receives air from inside the cab.
In general, a two piece molded roof structure is provided for enclosing the cab of a work vehicle. The roof structure has an upper roof member mounted to a lower roof member. The lower roof member has a plurality of contours and apertures for receiving the components of an HVAC system, and for defining air passages. When the upper and lower roof members are joined discrete air passages are formed between the roof members. The roof structure includes fresh and recirculated air intakes communicating via an unconditioned air duct and with an HVAC core chamber housing an HVAC core. Filters are mounted in the air intakes. One or more blowers communicate between the core chamber and a conditioned air duct which has vents communicating with the cab interior. Air is thus drawn in through the intakes and directed through the unconditioned air duct to the HVAC core and then the blower expels the air into the conditioned air duct and into the vehicle cab.
To acquaint persons skilled in the art most closely related to the present invention, one preferred embodiment of the invention that illustrates the best mode now contemplated for putting the invention into practice is described herein by and with reference to, the annexed drawings that form a part of the specification. The exemplary embodiment is described in detail without attempting to show all of the various forms and modifications in which the invention might be embodied. As such, the embodiment shown and described herein is illustrative, and as will become apparent to those skilled in the art, can be modified in numerous ways within the spirit and scope of the inventionxe2x80x94the invention being measured by the appended claims and not by the details of the specification.
For a complete understanding of the objects, techniques, and structure of the invention reference should be made to the following detailed description and accompanying drawings, wherein:
FIG. 1 is a perspective view of a portion of a vehicle cab showing the roof structure of the present invention;
FIG. 2 is a perspective view of the upper side of the lower roof member;
FIG. 3 is a perspective view of the lower side of the lower roof member;
FIG. 4 is an exploded perspective view showing the lower roof member and the components of the HVAC system;
FIG. 5 is an exploded perspective view of the upper side of the upper roof member; and,
FIG. 6 is a cross-sectional view of the roof structure of FIG. 1 taken along the line 6xe2x80x946.